Should You Get a 3D or 4D Ultrasound?

Most people will have at least one ultrasound done during pregnancy as part of their routine prenatal care. These ultrasounds are most often two-dimensional (2D), which means they provide a picture image of the fetus. Ultrasounds in a medical setting are a safe and effective tool for evaluating a fetus and diagnosing complications.

Ultrasounds performed for non-medical reasons, however, are typically not recommended. Health experts generally advise against "keepsake" three-dimensional (3D) and four-dimensional (4D) ultrasounds, which produce still and moving images of your baby in the uterus, because there is no medical benefit and the long-term effects of these lengthy ultrasound exposure are unknown.

2D Ultrasound

All ultrasounds use sound waves to create a picture. The traditional ultrasound used in pregnancy creates a 2D image of a developing fetus. 2D ultrasound produces outlines and flat-looking images, which can be used to see the baby's body and internal organs. 

2D ultrasounds have been used for decades and have an excellent safety record. Since these devices use non-ionizing radiation, they don't hold the same risks as X-rays, which use ionizing radiation.

Ultrasounds are routinely performed at least once in pregnancy, most commonly during the second trimester between 18 and 22 weeks. Known as a level II ultrasound or anatomy scan, this test is used to check in on how your baby is developing. 

Ultrasounds can be used to look at a variety of things during pregnancy, including:

• Any problems with the uterus, ovaries, cervix, or placenta
  
• Any problems you and/or your baby may be having
• The sex of the baby
  
• How many babies you're carrying
• How your baby is developing
• Signs of congenital abnormalities
  
• Signs of Down syndrome
• The level of amniotic fluid
  
• Your baby's gestational age
• Your baby's growth and position in the uterus
• Your baby's heart rate
  

3D Ultrasound

In recent years, 3D ultrasound images have become popular. However, unless medically indicated, 3D ultrasounds may not be covered by your insurance. 2D ultrasounds are typically used in medical settings because they can clearly show the internal organs of a developing fetus, though 3D may be useful in diagnosing a facial or skeletal abnormality.

3D ultrasounds produce their image by piecing together multiple 2D images taken at different angles. Many parents enjoy 3D images because they feel like they can see what their baby looks like better than what the flatter 2D images are able to show. Even so, experts like the Food and Drug Administration (FDA) and the American College of Obstetricians and Gynecologists (ACOG) advise against getting a 3D ultrasound just for fun.

In order to limit exposure to heat and radiation, the "as low as reasonably achievable" (ALARA) principle is what guides ultrasound technicians in a clinical setting. While ultrasound is considered safe, there is not enough evidence to ascertain what prolonged exposure to ultrasound may do to a fetus or a pregnant person.

In non-clinical settings, such as places that provide "keepsake" images, there is no guarantee how long the session will last or if the ultrasound machine will be operated properly.

4D Ultrasound

A 4D ultrasound is similar to a 3D ultrasound except that the image it generates is continuously updated, much like a moving image. This type of ultrasound is most often done for entertainment and not for medical reasons. 

The FDA does not recommend that you get ultrasounds for fun or bonding purposes because ultrasound is a medical device and should only be used for medical purposes. It is recommended to avoid non-medical settings that offer ultrasounds unless referred by your doctor or midwife as part of your prenatal care.

Keepsake Ultrasounds Cautions

Ultrasounds are not intended for sale or use outside of a medical setting. The American Institute of Ultrasound in Medicine (AIUM) discourages ultrasound for non-medical use. In addition, AIUM recommends that only appropriately trained and credentialed medical professionals perform ultrasound exams.

Exposure to Heat and Radiation

Even though ultrasound is considered safe, ultrasound exposes a pregnant person and their fetus to non-ionizing radiation. It can heat tissue slightly and cause small bubbles in body fluids and tissue.

In commercial settings, ultrasound use can last as long as an hour in order to obtain a video. Because of the potential risk that overuse could have on the fetus and the pregnant person, ultrasound should be limited to use only when medically necessary and performed by technicians who are medically credentialed.

Cost

Ultrasounds made in a commercial setting for entertainment or bonding purposes can cost as much as $200 or more. Unless medically indicated, 3D and 4D ultrasounds will likely not be covered by insurance, which means you'll need to pay for them out-of-pocket. 

Missed Diagnosis

Technicians in non-medical settings may not be trained to identify abnormalities or other potential complications. If you choose a non-medical ultrasound instead of an ultrasound provided by your doctor or midwife, you risk missing a diagnosis. Conversely, if the technician is untrained, they may indicate a concern that is actually typical and expected, which can lead to unnecessary anxiety.

A Word From Verywell

2D ultrasounds are performed as part of routine prenatal care in the United States. The appeal of 3D and 4D ultrasounds is understandable, however, they are typically medically unnecessary except in special cases and may present added risks. A number of health authorities including the FDA, ACOG, and AIUM advise against "keepsake" ultrasounds as a bonding experience or a memento.

If you choose to obtain a 3D or 4D ultrasound, remember that commercial ultrasound is not a substitute for professional prenatal care. Be sure to also receive the ultrasound(s) that are recommended by your healthcare provider.